Motor-driven surgical cutting and fastening instrument with tactile position feedback

ABSTRACT

A surgical cutting and fastening instrument is disclosed. According to various embodiments, the instrument includes an end effector comprising an elongate channel, a clamping member pivotably connected to the channel, and a moveable cutting instrument for traversing the channel to cut an object clamped in the end effector by the clamping member when the clamping member is in a clamped position. The instrument may also comprise a main drive shaft assembly for actuating the cutting instrument in the end effector, a gear drive train connected to the main drive shaft assembly, and a motor for actuating the gear drive train. The instrument may also includes a closure trigger and a firing trigger, separate from the closure trigger, for actuating the motor when the firing trigger is retracted. Also, the instrument may comprise a mechanical closure system connected to the closure trigger and to the clamping member for causing the clamping member to pivot to the clamped position when the closure trigger is retracted.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application claiming priority under35 U.S.C. § 120 to U.S. patent application Ser. No. 15/093,028, entitledMOTOR-DRIVEN FASTENING ASSEMBLY, filed Apr. 7, 2016, now U.S. PatentApplication Publication No. 2016/0220249, which is a continuationapplication claiming priority under 35 U.S.C. § 120 to U.S. patentapplication Ser. No. 13/656,257, entitled MOTOR-DRIVEN SURGICAL CUTTINGAND FASTENING INSTRUMENT WITH TACTILE POSITION FEEDBACK, filed Oct. 19,2012, which issued on Jun. 21, 2016 as U.S. Pat. No. 9,370,358, which isa continuation application claiming priority under 35 U.S.C. § 120 toSer. No. 13/151,501, entitled MOTOR-DRIVEN SURGICAL CUTTING ANDFASTENING INSTRUMENT WITH TACTILE POSITION FEEDBACK, filed Jun. 2, 2011,which issued on Oct. 23, 2012 as U.S. Pat. No. 8,292,155, which is acontinuation application claiming priority under 35 U.S.C. § 120 to U.S.patent application Ser. No. 11/344,024, entitled MOTOR-DRIVEN SURGICALCUTTING AND FASTENING INSTRUMENT WITH MECHANICAL CLOSURE SYSTEM, filedJan. 31, 2006, which issued on May 29, 2012 as U.S. Pat. No. 8,186,555,the entire disclosures of which are hereby incorporated by referenceherein.

The present application is also related to the following U.S. patentapplications, filed on Jan. 31, 2006, which are incorporated herein byreference:

MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH USERFEEDBACK SYSTEM; U.S. patent application Ser. No. 11/343,498, now U.S.Pat. No. 7,766,210;

MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH LOADINGFORCE FEEDBACK; U.S. patent application Ser. No. 11/343,573, now U.S.Pat. No. 7,416,101;

MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH TACTILEPOSITION FEEDBACK; U.S. patent application Ser. No. 11/344,035, now U.S.Pat. No. 7,422,139;

MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH ADAPTIVEUSER FEEDBACK; U.S. patent application Ser. No. 11/343,447, now U.S.Pat. No. 7,770,775;

MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITHARTICULATABLE END EFFECTOR; U.S. patent application Ser. No. 11/343,562,now U.S. Pat. No. 7,568,603;

SURGICAL CUTTING AND FASTENING INSTRUMENT WITH CLOSURE TRIGGER LOCKINGMECHANISM; U.S. patent application Ser. No. 11/343,321, now U.S. PatentApplication Publication No. 2007/0175955;

GEARING SELECTOR FOR A POWERED SURGICAL CUTTING AND FASTENING STAPLINGINSTRUMENT; U.S. patent application Ser. No. 11/343,563, now U.S. PatentApplication Publication No. 2007/0175951;

SURGICAL INSTRUMENT HAVING RECORDING CAPABILITIES; U.S. patentapplication Ser. No. 11/343,803, now U.S. Pat. No. 7,845,537;

SURGICAL INSTRUMENT HAVING A REMOVABLE BATTERY; U.S. patent applicationSer. No. 11/344,020, U.S. Pat. No. 7,464,846;

ELECTRONIC LOCKOUTS AND SURGICAL INSTRUMENT INCLUDING SAME; U.S. patentapplication Ser. No. 11/343,439, now U.S. Pat. No. 7,644,848;

ENDOSCOPIC SURGICAL INSTRUMENT WITH A HANDLE THAT CAN ARTICULATE WITHRESPECT TO THE SHAFT; U.S. patent application Ser. No. 11/343,547, nowU.S. Pat. No. 7,753,904;

ELECTRO-MECHANICAL SURGICAL CUTTING AND FASTENING INSTRUMENT HAVING AROTARY FIRING AND CLOSURE SYSTEM WITH PARALLEL CLOSURE AND ANVILALIGNMENT COMPONENTS; U.S. patent application Ser. No. 11/344,021, nowU.S. Pat. No. 7,464,849;

DISPOSABLE STAPLE CARTRIDGE HAVING AN ANVIL WITH TISSUE LOCATOR FOR USEWITH A SURGICAL CUTTING AND FASTENING INSTRUMENT AND MODULAR ENDEFFECTOR SYSTEM THEREFOR; U.S. patent application Ser. No. 11/343,546,now U.S. Patent Application Publication No. 2007/0175950; and

SURGICAL INSTRUMENT HAVING A FEEDBACK SYSTEM; U.S. patent applicationSer. No. 11/343,545, now U.S. Pat. No. 8,708,213.

BACKGROUND

The present invention generally concerns surgical cutting and fasteninginstruments and, more particularly, motor-driven surgical cutting andfastening instruments.

DRAWINGS

Various embodiments of the present invention are described herein by wayof example in conjunction with the following figures, wherein

FIGS. 1 and 2 are perspective views of a surgical cutting and fasteninginstrument according to various embodiments of the present invention;

FIGS.3-5 are exploded views of an end effector and shaft of theinstrument according to various embodiments of the present invention;

FIG. 6 is a side view of the end effector according to variousembodiments of the present invention;

FIG. 7 is an exploded view of the handle of the instrument according tovarious embodiments of the present invention;

FIGS. 8 and 9 are partial perspective views of the handle according tovarious embodiments of the present invention;

FIG. 10 is a side view of the handle according to various embodiments ofthe present invention;

FIG. 11 is a schematic diagram of a circuit used in the instrumentaccording to various embodiments of the present invention;

FIGS. 12-13 are side views of the handle according to other embodimentsof the present invention;

FIGS. 14-22 illustrate different mechanisms for locking the closuretrigger according to various embodiments of the present invention;

FIGS. 23A-B show a universal joint (“u-joint”) that may be employed atthe articulation point of the instrument according to variousembodiments of the present invention;

FIGS. 24A-B shows a torsion cable that may be employed at thearticulation point of the instrument according to various embodiments ofthe present invention;

FIGS. 25-31 illustrate a surgical cutting and fastening instrument withpower assist according to another embodiment of the present invention;

FIGS. 32-36 illustrate a surgical cutting and fastening instrument withpower assist according to yet another embodiment of the presentinvention;

FIGS. 37-40 illustrate a surgical cutting and fastening instrument withtactile feedback to embodiments of the present invention;

FIGS. 41-42 illustrate a proportional sensor that may be used accordingto various embodiments of the present invention;

FIG. 43 is a perspective view of a surgical cutting and fasteninginstrument that can employ various end effector embodiments and staplecartridge embodiments of the present invention;

FIG. 44 is a perspective view of an end effector embodiment of thepresent invention in a closed position;

FIG. 45 is a perspective view of the end effector of FIG. 44 in an openposition;

FIG. 46 is an exploded assembly view of an end effector embodiment ofthe present invention;

FIG. 47 is a cross sectional view of an end effector embodiment of thepresent invention supporting a staple cartridge therein with some of thecomponents thereof omitted for clarity;

FIG. 48 is a partial top view of a staple cartridge that may be employedin connection with various embodiments of the present invention;

FIG. 49 is a partial cross-sectional view of a staple cartridge and endeffector embodiment of the present invention illustrating the firing ofstaples into tissue clamped in the end effector;

FIG. 50 is a bottom perspective view of a portion of an end effectorembodiment of the present invention supporting a staple cartridgetherein;

FIG. 51 is a partial perspective view of an end effector embodiment ofthe present invention supporting a staple cartridge therein;

FIG. 52 is a perspective view of a distal drive shaft portion of variousembodiments of the present invention;

FIG. 53 is a cross-sectional view of the distal drive shaft portion ofFIG. 52;

FIG. 54 is a cross-sectional view of the distal drive shaft portion andclosure nut with the closure nut in an open position;

FIG. 55 is another cross-sectional view of the distal drive shaftportion and closure nut with the closure nut in the closed position;

FIG. 56 is a perspective view of a tapered clutch member of variousembodiments of the present invention;

FIG. 57 is a cross-sectional view of the tapered clutch member of FIG.56;

FIG. 58 is a perspective view of a clutch plate of various embodimentsof the present invention;

FIG. 59 is a cross-sectional view of the clutch plate of FIG. 58;

FIG. 60 is a perspective view of a closure nut of various embodiments ofthe present invention;

FIG. 61 is a cross-sectional view of the closure nut of FIG. 60;

FIG. 62 is a side elevational view of various end effector embodimentsof the present invention in an open position;

FIG. 63 is an enlarged partial cut away view of the end effector of FIG.62;

FIG. 64 is another enlarged partial cutaway view of the end effector ofFIG. 62;

FIG. 65 is a side elevational view of an end effector of the presentinvention in an open position clamping a piece of tissue therein;

FIG. 66 is an enlarged partial cut away view of the end effector of FIG.65;

FIG. 67 is a side elevational view of various end effector embodimentsof the present invention prior to being actuated to a closed position;

FIG. 68 is an enlarged partial cut away view of the end effector of FIG.67;

FIG. 69 is a side elevational view of various end effector embodimentsof the present invention in a closed position;

FIG. 70 is an enlarged partial cut away view of the end effector of FIG.69;

FIG. 71 is another enlarged partial cut away view of the end effector ofFIGS. 69 and 70;

FIG. 72 is a cross-sectional view of the end effector of FIGS. 69-71after the knife assembly has been driven to its distal-most position;

FIG. 73 is a cross-sectional view of the end effector of FIGS. 69-71;

FIG. 74 is a partial enlarged view of a portion of an end effector ofthe present invention;

FIG. 75 is a cross-sectional view of a control handle of variousembodiments of the present invention;

FIG. 76 is a partial cross-sectional view of a portion of another endeffector embodiment of the present invention in an open position; and

FIG. 77 is a partial cross-sectional view of the end effector of FIG. 76in a closed position.

DETAILED DESCRIPTION

FIGS. 1 and 2 depict a surgical cutting and fastening instrument 10according to various embodiments of the present invention. Theillustrated embodiment is an endoscopic instrument and, in general, theembodiments of the instrument 10 described herein are endoscopicsurgical cutting and fastening instruments. It should be noted, however,that according to other embodiments of the present invention, theinstrument may be a non-endoscopic surgical cutting and fasteninginstrument, such as a laparoscopic instrument.

The surgical instrument 10 depicted in FIGS. 1 and 2 comprises a handle6, a shaft 8, and an articulating end effector 12 pivotally connected tothe shaft 8 at an articulation pivot 14. An articulation control 16 maybe provided adjacent to the handle 6 to effect rotation of the endeffector 12 about the articulation pivot 14. In the illustratedembodiment, the end effector 12 is configured to act as an endocutterfor clamping, severing and stapling tissue, although, in otherembodiments, different types of end effectors may be used, such as endeffectors for other types of surgical devices, such as graspers,cutters, staplers, clip appliers, access devices, drug/gene therapydevices, ultrasound, RF or laser devices, etc.

The handle 6 of the instrument 10 may include a closure trigger 18 and afiring trigger 20 for actuating the end effector 12. It will beappreciated that instruments having end effectors directed to differentsurgical tasks may have different numbers or types of triggers or othersuitable controls for operating the end effector 12. The end effector 12is shown separated from the handle 6 by a preferably elongate shaft 8.In one embodiment, a clinician or operator of the instrument 10 mayarticulate the end effector 12 relative to the shaft 8 by utilizing thearticulation control 16, as described in more detail in U.S. patentapplication Ser. No. 11/329,020, filed Jan. 10, 2006, entitled SURGICALINSTRUMENT HAVING AN ARTICULATING END EFFECTOR, now U.S. Pat. No.7,670,334, which is incorporated herein by reference.

The end effector 12 includes in this example, among other things, astaple channel 22 and a pivotally translatable clamping member, such asan anvil 24, which are maintained at a spacing that assures effectivestapling and severing of tissue clamped in the end effector 12. Thehandle 6 includes a pistol grip 26 towards which a closure trigger 18 ispivotally drawn by the clinician to cause clamping or closing of theanvil 24 toward the staple channel 22 of the end effector 12 to therebyclamp tissue positioned between the anvil 24 and channel 22. The firingtrigger 20 is farther outboard of the closure trigger 18. Once theclosure trigger 18 is locked in the closure position as furtherdescribed below, the firing trigger 20 may rotate slightly toward thepistol grip 26 so that it can be reached by the operator using one hand.Then the operator may pivotally draw the firing trigger 20 toward thepistol grip 12 to cause the stapling and severing of clamped tissue inthe end effector 12. In other embodiments, different types of clampingmembers besides the anvil 24 could be used, such as, for example, anopposing jaw, etc.

It will be appreciated that the terms “proximal” and “distal” are usedherein with reference to a clinician gripping the handle 6 of aninstrument 10. Thus, the end effector 12 is distal with respect to themore proximal handle 6. It will be further appreciated that, forconvenience and clarity, spatial terms such as “vertical” and“horizontal” are used herein with respect to the drawings. However,surgical instruments are used in many orientations and positions, andthese terms are not intended to be limiting and absolute.

The closure trigger 18 may be actuated first. Once the clinician issatisfied with the positioning of the end effector 12, the clinician maydraw back the closure trigger 18 to its fully closed, locked positionproximate to the pistol grip 26. The firing trigger 20 may then beactuated. The firing trigger 20 returns to the open position (shown inFIGS. 1 and 2) when the clinician removes pressure, as described morefully below. A release button on the handle 6, when depressed mayrelease the locked closure trigger 18. The release button may beimplemented in various forms such as, for example, as a slide releasebutton 160 shown in FIG. 14, and/or button 172 shown in FIG. 16.

FIG. 3 is an exploded view of the end effector 12 according to variousembodiments. As shown in the illustrated embodiment, the end effector 12may include, in addition to the previously-mentioned channel 22 andanvil 24, a cutting instrument 32, a sled 33, a staple cartridge 34 thatis removably seated in the channel 22, and a helical screw shaft 36. Thecutting instrument 32 may be, for example, a knife. The anvil 24 may bepivotably opened and closed at a pivot point 25 connected to theproximate end of the channel 22. The anvil 24 may also include a tab 27at its proximate end that is inserted into a component of the mechanicalclosure system (described further below) to open and close the anvil 24.When the closure trigger 18 is actuated, that is, drawn in by a user ofthe instrument 10, the anvil 24 may pivot about the pivot point 25 intothe clamped or closed position. If clamping of the end effector 12 issatisfactory, the operator may actuate the firing trigger 20, which, asexplained in more detail below, causes the knife 32 and sled 33 totravel longitudinally along the channel 22, thereby cutting tissueclamped within the end effector 12. The movement of the sled 33 alongthe channel 22 causes the staples of the staple cartridge 34 to bedriven through the severed tissue and against the closed anvil 24, whichturns the staples to fasten the severed tissue. In various embodiments,the sled 33 may be an integral component of the cartridge 34. U.S. Pat.No. 6,978,921, entitled SURGICAL STAPLING INSTRUMENT INCORPORATING ANE-BEAM FIRING MECHANISM, which is incorporated herein by reference,provides more details about such two-stroke cutting and fasteninginstruments. The sled 33 may be part of the cartridge 34, such that whenthe knife 32 retracts following the cutting operation, the sled 33 doesnot retract.

It should be noted that although the embodiments of the instrument 10described herein employ an end effector 12 that staples the severedtissue, in other embodiments different techniques for fastening orsealing the severed tissue may be used. For example, end effectors thatuse RF energy or adhesives to fasten the severed tissue may also beused. U.S. Pat. No. 5,709,680 entitled ELECTROSURGICAL HEMOSTATICDEVICE, and U.S. Pat. No. 5,688,270 entitled ELECTROSURGICAL HEMOSTATICDEVICE WITH RECESSED AND/OR OFFSET ELECTRODES, which are incorporatedherein by reference, disclose an endoscopic cutting instrument that usesRF energy to seal the severed tissue. U.S. patent application Ser. No.11/267,811, now U.S. Pat. No. 7,673,783, and U.S. patent applicationSer. No. 11/267,383, now U.S. Pat. No. 7,607,557, which are alsoincorporated herein by reference, disclose an endoscopic cuttinginstrument that uses adhesives to fasten the severed tissue.Accordingly, although the description herein refers to cutting/staplingoperations and the like below, it should be recognized that this is anexemplary embodiment and is not meant to be limiting. Othertissue-fastening techniques may also be used.

FIGS. 4 and 5 are exploded views and FIG. 6 is a side view of the endeffector 12 and shaft 8 according to various embodiments. As shown inthe illustrated embodiment, the shaft 8 may include a proximate closuretube 40 and a distal closure tube 42 pivotably linked by a pivot links44. The distal closure tube 42 includes an opening 45 into which the tab27 on the anvil 24 is inserted in order to open and close the anvil 24,as further described below. Disposed inside the closure tubes 40, 42 maybe a proximate spine tube 46. Disposed inside the proximate spine tube46 may be a main rotational (or proximate) drive shaft 48 thatcommunicates with a secondary (or distal) drive shaft 50 via a bevelgear assembly 52. The secondary drive shaft 50 is connected to a drivegear 54 that engages a proximate drive gear 56 of the helical screwshaft 36. The vertical bevel gear 52 b may sit and pivot in an opening57 in the distal end of the proximate spine tube 46. A distal spine tube58 may be used to enclose the secondary drive shaft 50 and the drivegears 54, 56. Collectively, the main drive shaft 48, the secondary driveshaft 50, and the articulation assembly (e.g., the bevel gear assembly52 a-c) are sometimes referred to herein as the “main drive shaftassembly.”

A bearing 38, positioned at a distal end of the staple channel 22,receives the helical drive screw 36, allowing the helical drive screw 36to freely rotate with respect to the channel 22. The helical screw shaft36 may interface a threaded opening (not shown) of the knife 32 suchthat rotation of the shaft 36 causes the knife 32 to translate distallyor proximately (depending on the direction of the rotation) through thestaple channel 22. Accordingly, when the main drive shaft 48 is causedto rotate by actuation of the firing trigger 20 (as explained in moredetail below), the bevel gear assembly 52 a-c causes the secondary driveshaft 50 to rotate, which in turn, because of the engagement of thedrive gears 54, 56, causes the helical screw shaft 36 to rotate, whichcauses the knife driving member 32 to travel longitudinally along thechannel 22 to cut any tissue clamped within the end effector. The sled33 may be made of, for example, plastic, and may have a sloped distalsurface. As the sled 33 traverse the channel 22, the sloped forwardsurface may push up or drive the staples in the staple cartridge throughthe clamped tissue and against the anvil 24. The anvil 24 turns thestaples, thereby stapling the severed tissue. When the knife 32 isretracted, the knife 32 and sled 33 may become disengaged, therebyleaving the sled 33 at the distal end of the channel 22.

As described above, because of the lack of user feedback for thecutting/stapling operation, there is a general lack of acceptance amongphysicians of motor-driven endocutters where the cutting/staplingoperation is actuated by merely pressing a button. In contrast,embodiments of the present invention provide a motor-driven endocutterwith user-feedback of the deployment, force, and/or position of thecutting instrument in the end effector.

FIGS. 7-10 illustrate an exemplary embodiment of a motor-drivenendocutter, and in particular the handle thereof, that providesuser-feedback regarding the deployment and loading force of the cuttinginstrument in the end effector. In addition, the embodiment may usepower provided by the user in retracting the firing trigger 20 to powerthe device (a so-called “power assist” mode). As shown in theillustrated embodiment, the handle 6 includes exterior lower side pieces59, 60 and exterior upper side pieces 61, 62 that fit together to form,in general, the exterior of the handle 6. A battery 64, such as a Li ionbattery, may be provided in the pistol grip portion 26 of the handle 6.The battery 64 powers a motor 65 disposed in an upper portion of thepistol grip portion 26 of the handle 6. According to variousembodiments, the motor 65 may be a DC brushed driving motor having amaximum rotation of, approximately, 5000 RPM. The motor 64 may drive a90° bevel gear assembly 66 comprising a first bevel gear 68 and a secondbevel gear 70. The bevel gear assembly 66 may drive a planetary gearassembly 72. The planetary gear assembly 72 may include a pinion gear 74connected to a drive shaft 76. The pinion gear 74 may drive a matingring gear 78 that drives a helical gear drum 80 via a drive shaft 82. Aring 84 may be threaded on the helical gear drum 80. Thus, when themotor 65 rotates, the ring 84 is caused to travel along the helical geardrum 80 by means of the interposed bevel gear assembly 66, planetarygear assembly 72 and ring gear 78.

The handle 6 may also include a run motor sensor 110 in communicationwith the firing trigger 20 to detect when the firing trigger 20 has beendrawn in (or “closed”) toward the pistol grip portion 26 of the handle 6by the operator to thereby actuate the cutting/stapling operation by theend effector 12. The sensor 110 may be a proportional sensor such as,for example, a rheostat or variable resistor. When the firing trigger 20is drawn in, the sensor 110 detects the movement, and sends anelectrical signal indicative of the voltage (or power) to be supplied tothe motor 65. When the sensor 110 is a variable resistor or the like,the rotation of the motor 65 may be generally proportional to the amountof movement of the firing trigger 20. That is, if the operator onlydraws or closes the firing trigger 20 in a little bit, the rotation ofthe motor 65 is relatively low. When the firing trigger 20 is fullydrawn in (or in the fully closed position), the rotation of the motor 65is at its maximum. In other words, the harder the user pulls on thefiring trigger 20, the more voltage is applied to the motor 65, causinggreater rates of rotation.

The handle 6 may include a middle handle piece 104 adjacent to the upperportion of the firing trigger 20. The handle 6 also may comprise a biasspring 112 connected between posts on the middle handle piece 104 andthe firing trigger 20. The bias spring 112 may bias the firing trigger20 to its fully open position. In that way, when the operator releasesthe firing trigger 20, the bias spring 112 will pull the firing trigger20 to its open position, thereby removing actuation of the sensor 110,thereby stopping rotation of the motor 65. Moreover, by virtue of thebias spring 112, any time a user closes the firing trigger 20, the userwill experience resistance to the closing operation, thereby providingthe user with feedback as to the amount of rotation exerted by the motor65. Further, the operator could stop retracting the firing trigger 20 tothereby remove force from the sensor 100, to thereby stop the motor 65.As such, the user may stop the deployment of the end effector 12,thereby providing a measure of control of the cutting/fasteningoperation to the operator.

The distal end of the helical gear drum 80 includes a distal drive shaft120 that drives a ring gear 122, which mates with a pinion gear 124. Thepinion gear 124 is connected to the main drive shaft 48 of the maindrive shaft assembly. In that way, rotation of the motor 65 causes themain drive shaft assembly to rotate, which causes actuation of the endeffector 12, as described above.

The ring 84 threaded on the helical gear drum 80 may include a post 86that is disposed within a slot 88 of a slotted arm 90. The slotted arm90 has an opening 92 its opposite end 94 that receives a pivot pin 96that is connected between the handle exterior side pieces 59, 60. Thepivot pin 96 is also disposed through an opening 100 in the firingtrigger 20 and an opening 102 in the middle handle piece 104.

In addition, the handle 6 may include a reverse motor (or end-of-strokesensor) 130 and a stop motor (or beginning-of-stroke) sensor 142. Invarious embodiments, the reverse motor sensor 130 may be a limit switchlocated at the distal end of the helical gear drum 80 such that the ring84 threaded on the helical gear drum 80 contacts and trips the reversemotor sensor 130 when the ring 84 reaches the distal end of the helicalgear drum 80. The reverse motor sensor 130, when activated, sends asignal to the motor 65 to reverse its rotation direction, therebywithdrawing the knife 32 of the end effector 12 following the cuttingoperation.

The stop motor sensor 142 may be, for example, a normally-closed limitswitch. In various embodiments, it may be located at the proximate endof the helical gear drum 80 so that the ring 84 trips the switch 142when the ring 84 reaches the proximate end of the helical gear drum 80.

In operation, when an operator of the instrument 10 pulls back thefiring trigger 20, the sensor 110 detects the deployment of the firingtrigger 20 and sends a signal to the motor 65 to cause forward rotationof the motor 65 at, for example, a rate proportional to how hard theoperator pulls back the firing trigger 20. The forward rotation of themotor 65 in turn causes the ring gear 78 at the distal end of theplanetary gear assembly 72 to rotate, thereby causing the helical geardrum 80 to rotate, causing the ring 84 threaded on the helical gear drum80 to travel distally along the helical gear drum 80. The rotation ofthe helical gear drum 80 also drives the main drive shaft assembly asdescribed above, which in turn causes deployment of the knife 32 in theend effector 12. That is, the knife 32 and sled 33 are caused totraverse the channel 22 longitudinally, thereby cutting tissue clampedin the end effector 12. Also, the stapling operation of the end effector12 is caused to happen in embodiments where a stapling-type end effectoris used.

By the time the cutting/stapling operation of the end effector 12 iscomplete, the ring 84 on the helical gear drum 80 will have reached thedistal end of the helical gear drum 80, thereby causing the reversemotor sensor 130 to be tripped, which sends a signal to the motor 65 tocause the motor 65 to reverse its rotation. This in turn causes theknife 32 to retract, and also causes the ring 84 on the helical geardrum 80 to move back to the proximate end of the helical gear drum 80.

The middle handle piece 104 includes a backside shoulder 106 thatengages the slotted arm 90 as best shown in FIGS. 8 and 9. The middlehandle piece 104 also has a forward motion stop 107 that engages thefiring trigger 20. The movement of the slotted arm 90 is controlled, asexplained above, by rotation of the motor 65. When the slotted arm 90rotates CCW as the ring 84 travels from the proximate end of the helicalgear drum 80 to the distal end, the middle handle piece 104 will be freeto rotate CCW. Thus, as the user draws in the firing trigger 20, thefiring trigger 20 will engage the forward motion stop 107 of the middlehandle piece 104, causing the middle handle piece 104 to rotate CCW. Dueto the backside shoulder 106 engaging the slotted arm 90, however, themiddle handle piece 104 will only be able to rotate CCW as far as theslotted arm 90 permits. In that way, if the motor 65 should stoprotating for some reason, the slotted arm 90 will stop rotating, and theuser will not be able to further draw in the firing trigger 20 becausethe middle handle piece 104 will not be free to rotate CCW due to theslotted arm 90.

FIGS. 41 and 42 illustrate two states of a variable sensor that may beused as the run motor sensor 110 according to various embodiments of thepresent invention. The sensor 110 may include a face portion 280, afirst electrode (A) 282, a second electrode (B) 284, and a compressibledielectric material 286 (e.g., EAP) between the electrodes 282, 284. Thesensor 110 may be positioned such that the face portion 280 contacts thefiring trigger 20 when retracted. Accordingly, when the firing trigger20 is retracted, the dielectric material 286 is compressed, as shown inFIG. 42, such that the electrodes 282, 284 are closer together. Sincethe distance “b” between the electrodes 282, 284 is directly related tothe impedance between the electrodes 282, 284, the greater the distancethe more impedance, and the closer the distance the less impedance. Inthat way, the amount that the dielectric 286 is compressed due toretraction of the firing trigger 20 (denoted as force “F” in FIG. 42) isproportional to the impedance between the electrodes 282, 284, which canbe used to proportionally control the motor 65.

Components of an exemplary closure system for closing (or clamping) theanvil 24 of the end effector 12 by retracting the closure trigger 18 arealso shown in FIGS. 7-10. In the illustrated embodiment, the closuresystem includes a yoke 250 connected to the closure trigger 18 by a pin251 that is inserted through aligned openings in both the closuretrigger 18 and the yoke 250. A pivot pin 252, about which the closuretrigger 18 pivots, is inserted through another opening in the closuretrigger 18 which is offset from where the pin 251 is inserted throughthe closure trigger 18. Thus, retraction of the closure trigger 18causes the upper part of the closure trigger 18, to which the yoke 250is attached via the pin 251, to rotate CCW. The distal end of the yoke250 is connected, via a pin 254, to a first closure bracket 256. Thefirst closure bracket 256 connects to a second closure bracket 258.Collectively, the closure brackets 256, 258 define an opening in whichthe proximate end of the proximate closure tube 40 (see FIG. 4) isseated and held such that longitudinal movement of the closure brackets256, 258 causes longitudinal motion by the proximate closure tube 40.The instrument 10 also includes a closure rod 260 disposed inside theproximate closure tube 40. The closure rod 260 may include a window 261into which a post 263 on one of the handle exterior pieces, such asexterior lower side piece 59 in the illustrated embodiment, is disposedto fixedly connect the closure rod 260 to the handle 6. In that way, theproximate closure tube 40 is capable of moving longitudinally relativeto the closure rod 260. The closure rod 260 may also include a distalcollar 267 that fits into a cavity 269 in proximate spine tube 46 and isretained therein by a cap 271 (see FIG. 4).

In operation, when the yoke 250 rotates due to retraction of the closuretrigger 18, the closure brackets 256, 258 cause the proximate closuretube 40 to move distally (i.e., away from the handle end of theinstrument 10), which causes the distal closure tube 42 to movedistally, which causes the anvil 24 to rotate about the pivot point 25into the clamped or closed position. When the closure trigger 18 isunlocked from the locked position, the proximate closure tube 40 iscaused to slide proximately, which causes the distal closure tube 42 toslide proximately, which, by virtue of the tab 27 being inserted in thewindow 45 of the distal closure tube 42, causes the anvil 24 to pivotabout the pivot point 25 into the open or unclamped position. In thatway, by retracting and locking the closure trigger 18, an operator mayclamp tissue between the anvil 24 and channel 22, and may unclamp thetissue following the cutting/stapling operation by unlocking the closuretrigger 20 from the locked position.

FIG. 11 is a schematic diagram of an electrical circuit of theinstrument 10 according to various embodiments of the present invention.When an operator initially pulls in the firing trigger 20 after lockingthe closure trigger 18, the sensor 110 is activated, allowing current toflow there through. If the normally-open reverse motor sensor switch 130is open (meaning the end of the end effector stroke has not beenreached), current will flow to a single pole, double throw relay 132.Since the reverse motor sensor switch 130 is not closed, the inductor134 of the relay 132 will not be energized, so the relay 132 will be inits non-energized state. The circuit also includes a cartridge lockoutsensor 136. If the end effector 12 includes a staple cartridge 34, thesensor 136 will be in the closed state, allowing current to flow.Otherwise, if the end effector 12 does not include a staple cartridge34, the sensor 136 will be open, thereby preventing the battery 64 frompowering the motor 65.

When the staple cartridge 34 is present, the sensor 136 is closed, whichenergizes a single pole, single throw relay 138. When the relay 138 isenergized, current flows through the relay 136, through the variableresistor sensor 110, and to the motor 65 via a double pole, double throwrelay 140, thereby powering the motor 65 and allowing it to rotate inthe forward direction.

When the end effector 12 reaches the end of its stroke, the reversemotor sensor 130 will be activated, thereby closing the switch 130 andenergizing the relay 134. This causes the relay 134 to assume itsenergized state (not shown in FIG. 13), which causes current to bypassthe cartridge lockout sensor 136 and variable resistor 110, and insteadcauses current to flow to both the normally-closed double pole, doublethrow relay 142 and back to the motor 65, but in a manner, via the relay140, that causes the motor 65 to reverse its rotational direction.

Because the stop motor sensor switch 142 is normally-closed, currentwill flow back to the relay 134 to keep it closed until the switch 142opens. When the knife 32 is fully retracted, the stop motor sensorswitch 142 is activated, causing the switch 142 to open, therebyremoving power from the motor 65.

In other embodiments, rather than a proportional-type sensor 110, anon-off type sensor could be used. In such embodiments, the rate ofrotation of the motor 65 would not be proportional to the force appliedby the operator. Rather, the motor 65 would generally rotate at aconstant rate. But the operator would still experience force feedbackbecause the firing trigger 20 is geared into the gear drive train.

FIG. 12 is a side-view of the handle 6 of a power-assist motorizedendocutter according to another embodiment. The embodiment of FIG. 12 issimilar to that of FIGS. 7-10 except that in the embodiment of FIG. 12,there is not slotted arm connected to the ring 84 threaded on thehelical gear drum 80. Instead, in the embodiment of FIG. 12, the ring 84includes a sensor portion 114 that moves with the ring 84 as the ring 84advances down (and back) on the helical gear drum 80. The sensor portion114 includes a notch 116. The reverse motor sensor 130 may be located atthe distal end of the notch 116 and the stop motor sensor 142 may belocated at the proximate end of the notch 116. As the ring 84 moves downthe helical gear drum 80 (and back), the sensor portion 114 moves withit. Further, as shown in FIG. 12, the middle piece 104 may have an arm118 that extends into the notch 12.

In operation, as an operator of the instrument 10 retracts in the firingtrigger 20 toward the pistol grip 26, the run motor sensor 110 detectsthe motion and sends a signal to power the motor 65, which causes, amongother things, the helical gear drum 80 to rotate. As the helical geardrum 80 rotates, the ring 84 threaded on the helical gear drum 80advances (or retracts, depending on the rotation). Also, due to thepulling in of the firing trigger 20, the middle piece 104 is caused torotate CCW with the firing trigger 20 due to the forward motion stop 107that engages the firing trigger 20. The CCW rotation of the middle piece104 cause the arm 118 to rotate CCW with the sensor portion 114 of thering 84 such that the arm 118 stays disposed in the notch 116. When thering 84 reaches the distal end of the helical gear drum 80, the arm 118will contact and thereby trip the reverse motor sensor 130. Similarly,when the ring 84 reaches the proximate end of the helical gear drum 80,the arm will contact and thereby trip the stop motor sensor 142. Suchactions may reverse and stop the motor 65, respectively, as describedabove.

FIG. 13 is a side-view of the handle 6 of a power-assist motorizedendocutter according to another embodiment. The embodiment of FIG. 13 issimilar to that of FIGS. 7-10 except that in the embodiment of FIG. 13,there is no slot in the arm 90. Instead, the ring 84 threaded on thehelical gear drum 80 includes a vertical channel 126. Instead of a slot,the arm 90 includes a post 128 that is disposed in the channel 126. Asthe helical gear drum 80 rotates, the ring 84 threaded on the helicalgear drum 80 advances (or retracts, depending on the rotation). The arm90 rotates CCW as the ring 84 advances due to the post 128 beingdisposed in the channel 126, as shown in FIG. 13.

As mentioned above, in using a two-stroke motorized instrument, theoperator first pulls back and locks the closure trigger 18. FIGS. 14 and15 show one embodiment of a way to lock the closure trigger 18 to thepistol grip portion 26 of the handle 6. In the illustrated embodiment,the pistol grip portion 26 includes a hook 150 that is biased to rotateCCW about a pivot point 151 by a torsion spring 152. Also, the closuretrigger 18 includes a closure bar 154. As the operator draws in theclosure trigger 18, the closure bar 154 engages a sloped portion 156 ofthe hook 150, thereby rotating the hook 150 upward (or CW in FIGS.12-13) until the closure bar 154 completely passes the sloped portion156 passes into a recessed notch 158 of the hook 150, which locks theclosure trigger 18 in place. The operator may release the closuretrigger 18 by pushing down on a slide button release 160 on the back oropposite side of the pistol grip portion 26. Pushing down the slidebutton release 160 rotates the hook 150 CW such that the closure bar 154is released from the recessed notch 158.

FIG. 16 shows another closure trigger locking mechanism according tovarious embodiments. In the embodiment of FIG. 16, the closure trigger18 includes a wedge 160 having an arrow-head portion 161. The arrow-headportion 161 is biased downward (or CW) by a leaf spring 162. The wedge160 and leaf spring 162 may be made from, for example, molded plastic.When the closure trigger 18 is retracted, the arrow-head portion 161 isinserted through an opening 164 in the pistol grip portion 26 of thehandle 6. A lower chamfered surface 166 of the arrow-head portion 161engages a lower sidewall 168 of the opening 164, forcing the arrow-headportion 161 to rotate CCW. Eventually the lower chamfered surface 166fully passes the lower sidewall 168, removing the CCW force on thearrow-head portion 161, causing the lower sidewall 168 to slip into alocked position in a notch 170 behind the arrow-head portion 161.

To unlock the closure trigger 18, a user presses down on a button 172 onthe opposite side of the closure trigger 18, causing the arrow-headportion 161 to rotate CCW and allowing the arrow-head portion 161 toslide out of the opening 164.

FIGS. 17-22 show a closure trigger locking mechanism according toanother embodiment. As shown in this embodiment, the closure trigger 18includes a flexible longitudinal arm 176 that includes a lateral pin 178extending therefrom. The arm 176 and pin 178 may be made from moldedplastic, for example. The pistol grip portion 26 of the handle 6includes an opening 180 with a laterally extending wedge 182 disposedtherein. When the closure trigger 18 is retracted, the pin 178 engagesthe wedge 182, and the pin 178 is forced downward (i.e., the arm 176 isrotated CW) by the lower surface 184 of the wedge 182, as shown in FIGS.17 and 18. When the pin 178 fully passes the lower surface 184, the CWforce on the arm 176 is removed, and the pin 178 is rotated CCW suchthat the pin 178 comes to rest in a notch 186 behind the wedge 182, asshown in FIG. 19, thereby locking the closure trigger 18. The pin 178 isfurther held in place in the locked position by a flexible stop 188extending from the wedge 184.

To unlock the closure trigger 18, the operator may further squeeze theclosure trigger 18, causing the pin 178 to engage a sloped backwall 190of the opening 180, forcing the pin 178 upward past the flexible stop188, as shown in FIGS. 20 and 21. The pin 178 is then free to travel outan upper channel 192 in the opening 180 such that the closure trigger 18is no longer locked to the pistol grip portion 26, as shown in FIG.

FIGS. 23A-B show a universal joint (“u-joint”) 195. The second piece195-2 of the u-joint 195 rotates in a horizontal plane in which thefirst piece 195-1 lies. FIG. 23A shows the u-joint 195 in a linear(180°) orientation and FIG. 23B shows the u-joint 195 at approximately a150° orientation. The u-joint 195 may be used instead of the bevel gears52 a-c (see FIG. 4, for example) at the articulation point 14 of themain drive shaft assembly to articulate the end effector 12. FIGS. 24A-Bshow a torsion cable 197 that may be used in lieu of both the bevelgears 52 a-c and the u-joint 195 to realize articulation of the endeffector 12.

FIGS. 25-31 illustrate another embodiment of a motorized, two-strokesurgical cutting and fastening instrument 10 with power assist accordingto another embodiment of the present invention. The embodiment of FIGS.25-31 is similar to that of FIGS. 6-10 except that instead of thehelical gear drum 80, the embodiment of FIGS. 23-28 includes analternative gear drive assembly. The embodiment of FIGS. 25-31 includesa gear box assembly 200 including a number of gears disposed in a frame201, wherein the gears are connected between the planetary gear 72 andthe pinion gear 124 at the proximate end of the drive shaft 48. Asexplained further below, the gear box assembly 200 provides feedback tothe user via the firing trigger 20 regarding the deployment and loadingforce of the end effector 12. Also, the user may provide power to thesystem via the gear box assembly 200 to assist the deployment of the endeffector 12. In that sense, like the embodiments described above, theembodiment of FIGS. 23-32 is another power assist, motorized instrument10 that provides feedback to the user regarding the loading forceexperienced by the cutting instrument.

In the illustrated embodiment, the firing trigger 20 includes twopieces: a main body portion 202 and a stiffening portion 204. The mainbody portion 202 may be made of plastic, for example, and the stiffeningportion 204 may be made out of a more rigid material, such as metal. Inthe illustrated embodiment, the stiffening portion 204 is adjacent tothe main body portion 202, but according to other embodiments, thestiffening portion 204 could be disposed inside the main body portion202. A pivot pin 209 may be inserted through openings in the firingtrigger pieces 202, 204 and may be the point about which the firingtrigger 20 rotates. In addition, a spring 222 may bias the firingtrigger 20 to rotate in a CCW direction. The spring 222 may have adistal end connected to a pin 224 that is connected to the pieces 202,204 of the firing trigger 20. The proximate end of the spring 222 may beconnected to one of the handle exterior lower side pieces 59, 60.

In the illustrated embodiment, both the main body portion 202 and thestiffening portion 204 includes gear portions 206, 208 (respectively) attheir upper end portions. The gear portions 206, 208 engage a gear inthe gear box assembly 200, as explained below, to drive the main driveshaft assembly and to provide feedback to the user regarding thedeployment of the end effector 12.

The gear box assembly 200 may include as shown, in the illustratedembodiment, six (6) gears. A first gear 210 of the gear box assembly 200engages the gear portions 206, 208 of the firing trigger 20. Inaddition, the first gear 210 engages a smaller second gear 212, thesmaller second gear 212 being coaxial with a large third gear 214. Thethird gear 214 engages a smaller fourth gear 216, the smaller fourthgear being coaxial with a fifth gear 218. The fifth gear 218 is a 90°bevel gear that engages a mating 90° bevel gear 220 (best shown in FIG.31) that is connected to the pinion gear 124 that drives the main driveshaft 48.

In operation, when the user retracts the firing trigger 20, a run motorsensor (not shown) is activated, which may provide a signal to the motor65 to rotate at a rate proportional to the extent or force with whichthe operator is retracting the firing trigger 20. This causes the motor65 to rotate at a speed proportional to the signal from the sensor. Thesensor is not shown for this embodiment, but it could be similar to therun motor sensor 110 described above. The sensor could be located in thehandle 6 such that it is depressed when the firing trigger 20 isretracted. Also, instead of a proportional-type sensor, an on/off typesensor may be used.

Rotation of the motor 65 causes the bevel gears 66, 70 to rotate, whichcauses the planetary gear 72 to rotate, which causes, via the driveshaft 76, the ring gear 122 to rotate. The ring gear 122 meshes with thepinion gear 124, which is connected to the main drive shaft 48. Thus,rotation of the pinion gear 124 drives the main drive shaft 48, whichcauses actuation of the cutting/stapling operation of the end effector12.

Forward rotation of the pinion gear 124 in turn causes the bevel gear220 to rotate, which causes, by way of the rest of the gears of the gearbox assembly 200, the first gear 210 to rotate. The first gear 210engages the gear portions 206, 208 of the firing trigger 20, therebycausing the firing trigger 20 to rotate CCW when the motor 65 providesforward drive for the end effector 12 (and to rotate CCW when the motor65 rotates in reverse to retract the end effector 12). In that way, theuser experiences feedback regarding loading force and deployment of theend effector 12 by way of the user's grip on the firing trigger 20.Thus, when the user retracts the firing trigger 20, the operator willexperience a resistance related to the load force experienced by the endeffector 12. Similarly, when the operator releases the firing trigger 20after the cutting/stapling operation so that it can return to itsoriginal position, the user will experience a CW rotation force from thefiring trigger 20 that is generally proportional to the reverse speed ofthe motor 65.

It should also be noted that in this embodiment the user can apply force(either in lieu of or in addition to the force from the motor 65) toactuate the main drive shaft assembly (and hence the cutting/staplingoperation of the end effector 12) through retracting the firing trigger20. That is, retracting the firing trigger 20 causes the gear portions206, 208 to rotate CCW, which causes the gears of the gear box assembly200 to rotate, thereby causing the pinion gear 124 to rotate, whichcauses the main drive shaft 48 to rotate.

Although not shown in FIGS. 25-31, the instrument 10 may further includereverse motor and stop motor sensors. As described above, the reversemotor and stop motor sensors may detect, respectively, the end of thecutting stroke (full deployment of the knife/sled driving member 32) andthe end of retraction operation (full retraction of the knife/sleddriving member 32). A similar circuit to that described above inconnection with FIG. 11 may be used to appropriately power the motor 65.

FIGS. 32-36 illustrate a two-stroke, motorized surgical cutting andfastening instrument 10 with power assist according to anotherembodiment. The embodiment of FIGS. 32-36 is similar to that of FIGS.25-31 except that in the embodiment of FIGS. 32-36, the firing trigger20 includes a lower portion 228 and an upper portion 230. Both portions228, 230 are connected to and pivot about a pivot pin 207 that isdisposed through each portion 228, 230. The upper portion 230 includes agear portion 232 that engages the first gear 210 of the gear boxassembly 200. The spring 222 is connected to the upper portion 230 suchthat the upper portion is biased to rotate in the CW direction. Theupper portion 230 may also include a lower arm 234 that contacts anupper surface of the lower portion 228 of the firing trigger 20 suchthat when the upper portion 230 is caused to rotate CW the lower portion228 also rotates CW, and when the lower portion 228 rotates CCW theupper portion 230 also rotates CCW. Similarly, the lower portion 228includes a rotational stop 238 that engages a lower shoulder of theupper portion 230. In that way, when the upper portion 230 is caused torotate CCW the lower portion 228 also rotates CCW, and when the lowerportion 228 rotates CW the upper portion 230 also rotates CW.

The illustrated embodiment also includes the run motor sensor 110 thatcommunicates a signal to the motor 65 that, in various embodiments, maycause the motor 65 to rotate at a speed proportional to the forceapplied by the operator when retracting the firing trigger 20. Thesensor 110 may be, for example, a rheostat or some other variableresistance sensor, as explained herein. In addition, the instrument 10may include a reverse motor sensor 130 that is tripped or switched whencontacted by a front face 242 of the upper portion 230 of the firingtrigger 20. When activated, the reverse motor sensor 130 sends a signalto the motor 65 to reverse direction. Also, the instrument 10 mayinclude a stop motor sensor 142 that is tripped or actuated whencontacted by the lower portion 228 of the firing trigger 20. Whenactivated, the stop motor sensor 142 sends a signal to stop the reverserotation of the motor 65.

In operation, when an operator retracts the closure trigger 18 into thelocked position, the firing trigger 20 is retracted slightly (throughmechanisms known in the art, including U.S. Pat. Nos. 6,978,921 and6,905,057, which are incorporated herein by reference) so that the usercan grasp the firing trigger 20 to initiate the cutting/staplingoperation, as shown in FIGS. 32 and 33. At that point, as shown in FIG.33, the gear portion 232 of the upper portion 230 of the firing trigger20 moves into engagement with the first gear 210 of the gear boxassembly 200. When the operator retracts the firing trigger 20,according to various embodiments, the firing trigger 20 may rotate asmall amount, such as five degrees, before tripping the run motor sensor110, as shown in FIG. 34. Activation of the sensor 110 causes the motor65 to forward rotate at a rate proportional to the retraction forceapplied by the operator. The forward rotation of the motor 65 causes, asdescribed above, the main drive shaft 48 to rotate, which causes theknife 32 in the end effector 12 to be deployed (i.e., begin traversingthe channel 22). Rotation of the pinion gear 124, which is connected tothe main drive shaft 48, causes the gears 210-220 in the gear boxassembly 200 to rotate. Since the first gear 210 is in engagement withthe gear portion 232 of the upper portion 230 of the firing trigger 20,the upper portion 232 is caused to rotate CCW, which causes the lowerportion 228 to also rotate CCW.

When the knife 32 is fully deployed (i.e., at the end of the cuttingstroke), the front face 242 of the upper portion 230 trips the reversemotor sensor 130, which sends a signal to the motor 65 to reverserotational directional. This causes the main drive shaft assembly toreverse rotational direction to retract the knife 32. Reverse rotationof the main drive shaft assembly causes the gears 210-220 in the gearbox assembly to reverse direction, which causes the upper portion 230 ofthe firing trigger 20 to rotate CW, which causes the lower portion 228of the firing trigger 20 to rotate CW until the lower portion 228 tripsor actuates the stop motor sensor 142 when the knife 32 is fullyretracted, which causes the motor 65 to stop. In that way, the userexperiences feedback regarding deployment of the end effector 12 by wayof the user's grip on the firing trigger 20. Thus, when the userretracts the firing trigger 20, the operator will experience aresistance related to the deployment of the end effector 12 and, inparticular, to the loading force experienced by the knife 32. Similarly,when the operator releases the firing trigger 20 after thecutting/stapling operation so that it can return to its originalposition, the user will experience a CW rotation force from the firingtrigger 20 that is generally proportional to the reverse speed of themotor 65.

It should also be noted that in this embodiment the user can apply force(either in lieu of or in addition to the force from the motor 65) toactuate the main drive shaft assembly (and hence the cutting/staplingoperation of the end effector 12) through retracting the firing trigger20. That is, retracting the firing trigger 20 causes the gear portion232 of the upper portion 230 to rotate CCW, which causes the gears ofthe gear box assembly 200 to rotate, thereby causing the pinion gear 124to rotate, which causes the main drive shaft assembly to rotate.

The above-described embodiments employed power-assist user feedbacksystems, with or without adaptive control (e.g., using a sensor 110,130, and 142 outside of the closed loop system of the motor, gear drivetrain, and end effector) for a two-stroke, motorized surgical cuttingand fastening instrument. That is, force applied by the user inretracting the firing trigger 20 may be added to the force applied bythe motor 65 by virtue of the firing trigger 20 being geared into(either directly or indirectly) the gear drive train between the motor65 and the main drive shaft 48. In other embodiments of the presentinvention, the user may be provided with tactile feedback regarding theposition of the knife 32 in the end effector, but without having thefiring trigger 20 geared into the gear drive train. FIGS. 37-40illustrate a motorized surgical cutting and fastening instrument withsuch a tactile position feedback system.

In the illustrated embodiment of FIGS. 37-40, the firing trigger 20 mayhave a lower portion 228 and an upper portion 230, similar to theinstrument 10 shown in FIGS. 32-36. Unlike the embodiment of FIGS.32-36, however, the upper portion 230 does not have a gear portion thatmates with part of the gear drive train. Instead, the instrumentincludes a second motor 265 with a threaded rod 266 threaded therein.The threaded rod 266 reciprocates longitudinally in and out of the motor265 as the motor 265 rotates, depending on the direction of rotation.The instrument 10 also includes an encoder 268 that is responsive to therotations of the main drive shaft 48 for translating the incrementalangular motion of the main drive shaft 48 (or other component of themain drive assembly) into a corresponding series of digital signals, forexample. In the illustrated embodiment, the pinion gear 124 includes aproximate drive shaft 270 that connects to the encoder 268.

The instrument 10 also includes a control circuit (not shown), which maybe implemented using a microcontroller or some other type of integratedcircuit, that receives the digital signals from the encoder 268. Basedon the signals from the encoder 268, the control circuit may calculatethe stage of deployment of the knife 32 in the end effector 12. That is,the control circuit can calculate if the knife 32 is fully deployed,fully retracted, or at an intermittent stage. Based on the calculationof the stage of deployment of the end effector 12, the control circuitmay send a signal to the second motor 265 to control its rotation tothereby control the reciprocating movement of the threaded rod 266.

In operation, as shown in FIG. 37, when the closure trigger 18 is notlocked into the clamped position, the firing trigger 20 rotated awayfrom the pistol grip portion 26 of the handle 6 such that the front face242 of the upper portion 230 of the firing trigger 20 is not in contactwith the proximate end of the threaded rod 266. When the operatorretracts the closure trigger 18 and locks it in the clamped position,the firing trigger 20 rotates slightly towards the closure trigger 20 sothat the operator can grasp the firing trigger 20, as shown in FIG. 38.In this position, the front face 242 of the upper portion 230 contactsthe proximate end of the threaded rod 266.

As the user then retracts the firing trigger 20, after an initialrotational amount (e.g., 5 degrees of rotation) the run motor sensor 110may be activated such that, as explained above, the sensor 110 sends asignal to the motor 65 to cause it to rotate at a forward speedproportional to the amount of retraction force applied by the operatorto the firing trigger 20. Forward rotation of the motor 65 causes themain drive shaft 48 to rotate via the gear drive train, which causes theknife 32 and sled 33 to travel down the channel 22 and sever tissueclamped in the end effector 12. The control circuit receives the outputsignals from the encoder 268 regarding the incremental rotations of themain drive shaft assembly and sends a signal to the second motor 265 tocaused the second motor 265 to rotate, which causes the threaded rod 266to retract into the motor 265. This allows the upper portion 230 of thefiring trigger 20 to rotate CCW, which allows the lower portion 228 ofthe firing trigger to also rotate CCW. In that way, because thereciprocating movement of the threaded rod 266 is related to therotations of the main drive shaft assembly, the operator of theinstrument 10, by way of his/her grip on the firing trigger 20,experiences tactile feedback as to the position of the end effector 12.The retraction force applied by the operator, however, does not directlyaffect the drive of the main drive shaft assembly because the firingtrigger 20 is not geared into the gear drive train in this embodiment.

By virtue of tracking the incremental rotations of the main drive shaftassembly via the output signals from the encoder 268, the controlcircuit can calculate when the knife 32 is fully deployed (i.e., fullyextended). At this point, the control circuit may send a signal to themotor 65 to reverse direction to cause retraction of the knife 32. Thereverse direction of the motor 65 causes the rotation of the main driveshaft assembly to reverse direction, which is also detected by theencoder 268. Based on the reverse rotation detected by the encoder 268,the control circuit sends a signal to the second motor 265 to cause itto reverse rotational direction such that the threaded rod 266 starts toextend longitudinally from the motor 265. This motion forces the upperportion 230 of the firing trigger 20 to rotate CW, which causes thelower portion 228 to rotate CW. In that way, the operator may experiencea CW force from the firing trigger 20, which provides feedback to theoperator as to the retraction position of the knife 32 in the endeffector 12. The control circuit can determine when the knife 32 isfully retracted. At this point, the control circuit may send a signal tothe motor 65 to stop rotation.

According to other embodiments, rather than having the control circuitdetermine the position of the knife 32, reverse motor and stop motorsensors may be used, as described above. In addition, rather than usinga proportional sensor 110 to control the rotation of the motor 65, anon/off switch or sensor can be used. In such an embodiment, the operatorwould not be able to control the rate of rotation of the motor 65.Rather, it would rotate at a preprogrammed rate.

The various embodiments of the present invention have been describedabove in connection with cutting-type surgical instruments. It should benoted, however, that in other embodiments, the inventive surgicalinstrument disclosed herein need not be a cutting-type surgicalinstrument. For example, it could be a non-cutting endoscopicinstrument, a grasper, a stapler, a clip applier, an access device, adrug/gene therapy delivery device, an energy device using ultrasound,RF, laser, etc.

FIG. 43 depicts a surgical cutting and fastening instrument 2010 that iscapable of practicing various unique benefits of the end effectors anddrive arrangements of the present invention. The surgical instrument2010 depicted in FIG. 43 comprises a handle 2006, a shaft assembly 2008,and an articulating end effector 2300 pivotally connected to the shaftassembly 2008 at an articulation pivot 2014. In various embodiments, thecontrol handle houses a drive motor 2600 and control system generallyrepresented as 2610 therein for controlling the opening and closing ofthe end effector 2300 and the cutting and stapling of the tissue clampedtherein. An articulation control 2016 may be provided adjacent to thehandle 2006 to effect rotation of the end effector 2300 about thearticulation pivot 2014. The handle 2006 of the instrument 2010 mayinclude a closure trigger 2018 and a firing trigger 2020 for actuatingthe end effector 2300. The end effector 2300 is shown separated from thehandle 2006 preferably by an elongate shaft 2008. In one embodiment, aclinician or operator of the instrument 2010 may articulate the endeffector 2300 relative to a proximal portion of the shaft 2008 byutilizing the articulation control 2016, as described in more detail inU.S. patent application Ser. No. 11/329,020, filed Jan. 10, 2006,entitled SURGICAL INSTRUMENT HAVING AN ARTICULATING END EFFECTOR, nowU.S. Pat. No. 7,670,334. Other articulation arrangements could also beemployed.

As will be discussed in further detail below, various end effectorembodiments include an anvil 2340, which is maintained at a spacing thatassures effective stapling and severing of tissue clamped in the endeffector 2300. In various exemplary embodiments, the handle 2006 mayinclude a pistol grip 2026 towards which a closure trigger 2018 ispivotally drawn by the clinician to cause clamping or closing of theanvil 2340 toward cartridge 2500 seated in an elongate channel 2302 ofthe end effector 2300 to thereby clamp tissue positioned between theanvil 2340 and the staple cartridge 2500. A firing trigger 2020 may besituated farther outboard of the closure trigger 2018. In variousembodiments, once the closure trigger 2018 is locked in the closureposition as further described below, the firing trigger 2020 may rotateslightly toward the pistol grip 2026 so that it can be reached by theoperator using one hand. Then the operator may pivotally draw the firingtrigger 2020 toward the pistol grip 2026 to cause the stapling andsevering of clamped tissue in the end effector 2300. Those of ordinaryskill in the art will readily appreciate however, that other handle anddrive system arrangements may be successfully employed in connectionwith various embodiments described herein and their equivalentstructures without departing from the spirit and scope of the presentinvention.

It will be appreciated that the terms “proximal” and “distal” are usedherein with reference to a clinician gripping the handle 2006 of aninstrument 2010. Thus, the end effector 2300 is distal with respect tothe more proximal handle 2006. It will be further appreciated that, forconvenience and clarity, spatial terms such as “vertical” and“horizontal” are used herein with respect to the drawings. However,surgical instruments are used in many orientations and positions, andthese terms are not intended to be limiting and absolute.

FIGS. 43-47 illustrate a unique and novel end effector 2300 of variousembodiments of the present invention adapted for use with a staplecartridge 2500, the basic operation of which is known in the art. Forexample, U.S. Pat. No. 6,978,921, entitled SURGICAL STAPLING INSTRUMENTINCORPORATING AN E-BEAM FIRING MECHANISM, provides more details aboutthe construction of such staple cartridges.

In general, such staple cartridges 2500 include a cartridge body 2502that is divided by a central, elongated slot 2508 which extends from theproximal end 2504 of the cartridge body 2502 towards its tapered outertip 2506. See FIG. 46. The cartridge body 2502 may be fabricated from apolymeric material and be attached to a metal cartridge pan 2510. Aplurality of staple-receiving pockets 2512 are formed within thecartridge body 2502 and are arranged in six laterally spacedlongitudinal rows or “lines” of staples 2514, 2516, 2518, 2520, 2522,2524. See FIG. 48. Positioned within the pockets 2512 arestaple-supporting drivers 2532 which support staples 2534 thereon.Depending upon the location (line) of staple-receiving pockets 2512, thestaple supporting drivers 2532 may support one or two staples 2530thereon. The cartridge body 2502 further includes four longitudinalslots 2503, 2505, 2507, 2509 extending from its proximal end 2504 to itstapered outer tip 2506 for receiving corresponding sled cams 2328 formedon a wedge sled 2326 in the end effector 2300, the construction andoperation of which will discussed in further detail below. See FIG. 47.As the sled cams 2328 are advanced through their respective slots 2503,2505, 2507, 2509 in the cartridge body 2502 from proximal end 2504 todistal end 2506, they contact the staple-supporting drivers 2532associated with those slots and force the staple-supporting drivers 2532and the staples 2534 that they support upward out of the cartridge body2502. See FIG. 49. As the ends of the legs 2536 of the staple 2534contact the pockets 2350 formed in the bottom surface 2341 of the anvil2340, they are folded over to close the staples 2534.

Various end effectors of the present invention include an elongatechannel 2302 that is sized to removably receive and support thecartridge body 2502 and pan 2510 of a disposable cartridge 2500 therein.A knife screw 2304 is rotatably supported in the elongate channel 2302.The knife screw 2304 has a distal end 2306 that has a distal thrustbearing 2308 attached thereto that is rotatably supported by a distalbearing housing 2310 formed in the distal end 2303 of the elongatechannel 2302. See FIG. 46. The knife screw 2304 has a central driveportion 2312 with a helical thread formed thereon. The knife screw 2304further has a smooth extension portion 2314 and a knife screw gear 2316formed thereon or otherwise attached thereto. A proximal thrust bearing2318 is formed or attached to the proximal end 2317 of the knife screw2304. The proximal thrust bearing 2318 is rotatably housed within aproximal bearing housing 2319 supported in a distal spine tube segment2058. The distal spine tube segment 2058 has a pair of columns 2059formed on its distal end that are adapted to be received in verticalslots 2307 formed in the proximal end 2305 of the elongate channel 2302.The columns 2059 may be retained within the slots 2307 in the elongatechannel 2302 by friction, adhesive, or by the distal end of the shafttube 2009. See FIGS. 43 and 46.

Various embodiments of the present invention further include a knifeassembly 2320 that has a knife/sled bearing 2322 that is threaded ontothe threaded portion 2312 of the knife screw 2304. The knife assembly2320 supports a vertically extending blade 2324 and a wedge sled 2326that supports the four sled cams 2328. The reader will understand that,as the knife screw 2304 is rotated in a clockwise direction, the knifeassembly 2320 and the wedge sled 2326 is advanced toward the distal end2303 (direction “A”) of the elongate channel 2302 and, when the knifescrew 2304 is rotated in a counterclockwise direction, the knifeassembly 2320 and wedge sled 2326 is moved toward the proximal end 2305of the channel member 2302 (direction “B”). In addition, the knifeassembly 2320 has a pair of laterally extending deflector tabs 2330protruding therefrom, the purpose of which will be discussed below.

In various embodiments of the present invention, an anvil 2340 ispivotally coupled to the proximal end 2305 of the channel member 2302 bya pair of trunnion tabs 2342 that are sized to be received inoval-shaped pivot holes 2700 provided through the side walls 2309 of theelongate channel 2302. In various embodiments, the anvil 2340 may bestamped from sheet metal or other material such that the trunnion tabs2342 are substantially rectangular or square shaped. In otherembodiments, the anvil 2340 may be molded or machined from othermaterials such that it is rigid in nature and the trunnion tabs or pinsare substantially round. As can be seen in FIGS. 49 and 73, the bottomsurface 2341 of the anvil 2340 has a series of staple forming pockets2350 formed therein. It will be understood that the staple formingpockets 2350 serve to close the staples 2534 as the ends of the staplelegs 2536 are forced into contact therewith. In addition, a longitudinalclearance slot 2343 may be provided in the bottom surface 2341 of theanvil 2340 for receiving the upper end of the knife assembly 2320 andthe guide tabs 2330 therethrough such that the laterally extending guidetabs 2330 serve to urge the anvil 2340 down onto the elongated channel2302 as the knife assembly 2320 and wedge sled 2326 are driven throughthe cartridge 2500 to cut the tissue and deploy the staples 2534.

A drive assembly for operating various embodiments of the end effector2300 will now be described. In various embodiments, a distal drive shaftportion 2402 extends through a drive shaft hole 2061 in the distal spinetube 2058. See FIG. 46. The distal drive shaft portion 2402 may extenddirectly to a drive motor arrangement 2600 in the control handle 2006 orit may be articulated to enable the end effector 2300 to be pivotedrelative to the shaft or closure tube assembly that connects the endeffector 2300 to the control handle 2006.

As can be seen in FIGS. 52-55, in various embodiments of the presentinvention the distal drive shaft portion 2402 has a clutch-receivingportion 2404 and a closure thread 2406 formed thereon. A clutch assembly2410 is slidably received on the clutch-receiving portion 2404 of thedrive shaft portion 2402. In various embodiments, the clutch assembly2410 includes a collet-like tapered clutch member 2412 that has a drivegear 2414 integrally formed on its proximal end 2413. See FIGS. 56 and57. The drive gear 2414 meshes with a transfer gear 2450 that in turnmeshes with the knife screw gear 2316. See FIGS. 50 and 51. Thus, whenthe clutch assembly 2410 drivingly engages the distal drive shaftportion 2402, the drive gear 2414 rotates the transfer gear 2450 which,in turn rotates the knife screw gear 2316.

A series of four tapered sections 2416 are formed on the distal end 2415of the tapered clutch member 2412. A series of male splines 2418 areformed in the interior of the tapered sections 2416. See FIGS. 56 and57. The male splines 2418 are adapted to selectively engage a femalespline section 2408 formed on the distal drive shaft portion 2402 aswill be discussed in further detail below. See FIGS. 52-55. The clutchassembly 2410 further includes a clutch plate 2420 that is received onthe tapered sections 2416 of the tapered clutch member 2412. As can beseen in FIGS. 58 and 59, the clutch plate 2420 has a proximal hubportion 2422 and a distal hub portion 2424 that is separated by a flangeportion 2426. A cylindrical distal hole portion 2428 extends through thedistal hub portion 2424 and a tapered proximal hole 2430 extends throughthe flange portion 2426 and the proximal hub portion 2422. The holeportions 2428, 2430 enable the clutch plate 2420 to be slidably receivedon the drive shaft 2402 and slide onto the tapered clutch member 2412. Aclutch opening spring 2432 is provided between a flange portion 2417formed on the tapered clutch member 2412 and the flange portion 2426 ofthe clutch plate 2420 and a thrust bearing 2434 is also journaled on theclutch-receiving portion 2404 adjacent to the clutch plate 2420. SeeFIGS. 63 and 64.

Also in various embodiments, a closure nut 2440 is received on thedistal drive shaft portion 2402. As can be seen in FIGS. 54, 55, 60 and61, the closure nut 2440 has a threaded hole portion 2442 extendingpartially therethrough to enable it to be threaded onto the closurethread 2406 on the distal drive shaft portion 2402. As can be furtherseen in those Figures, the closure nut 2440 has an upstanding closureramp 2444 protruding therefrom. The top of the closure ramp 2444terminates in a radiused portion 2446 that extends to an upstandingclosure tab 2448 that is adapted to engage a downwardly protrudingclosure hook 2346 formed on the proximal end 2345 of anvil 2340.

More specifically and with reference to FIG. 63, the proximal end 2345of the anvil 2340 has an anvil closure arm portion 2347 protrudingproximally therefrom that terminates in a downwardly extending closurehook 2346. As can also be seen in that Figure, the bottom surface of theanvil closure arm 2347 has a tab relief groove 2348 therein forreceiving the closure tab 2348 when the closure nut 2440 is advanced toits most distal position (shown in FIGS. 69-72). Also in variousembodiments, a closure lock spring 2460 is attached to the bottom of theelongate channel 2302, by mechanical fastener arrangements or adhesive.The closure lock spring 2460 has an upper portion 2462 that terminatesin an upstanding retainer lip 2464. In addition, longitudinallyextending retainer arm 2466 is rigidly attached to the upper portion2462 of the closure lock spring 2460. See FIG. 46.

Various embodiments of the present invention employ an anvil 2340 thatis capable of moving axially and laterally relative to the elongatechannel 2302 prior to being advanced to the closed position. Morespecifically and with reference to FIGS. 62-72, in various embodiments,the elongate channel 2302 is stamped or otherwise formed from sheetmetal or the like and the pivot holes may be punched therein. Suchconstruction leads to reduced manufacturing costs for the end effector.Other embodiments may be machined from rigid materials such as 2416stainless steel such that the trunnion pins are substantially round incross-section. Regardless of which manufacturing method is employed tomanufacture the anvil 2340 and the resulting shape of the trunnion tabs2342, as can be seen in FIGS. 63, 66, 68, 70, and 74, the pivot holes2700 are oval or oblong and serve to afford the trunnion tabs 2342 withthe ability to move axially back and forth and up and down in theircorresponding pivot hole 2700. As can be seen in FIG. 74, the trunniontabs 2342 may have a length “X” of, for example, approximately 0.060inches and a height “Y” of, for example, approximately 0.050 inches. Thepivot holes 2700 have a proximal wall portion 2702, a distal wallportion 2704, an upper wall portion 2706 and a lower wall portion 2708.In various embodiments, for example, the distance “L” between theproximal wall 2702 and the distal wall 2704 may be approximately 0.120inches and the distance “H” between the upper wall portion 2706 andlower wall portion 2708 may be approximately 0.090 inches. See FIG. 74.Those of ordinary skill in the art will appreciate that these distancesand tolerances may, in connection with various embodiments, be somewhatdictated by the manufacturing tolerances attainable by the processesused to manufacture the anvil 2340 and the elongate channel 2302. Inother embodiments, however, the distances “H”, “L”, “X”, and “Y” may besized relative to each other to enable the anvil 2340 to travel along aclosing path that is relatively substantially parallel to the topsurface of a cartridge 2500 supported in the elongate channel 2302. Sucharrangement serves to prevent or minimize the likelihood of tissue frombeing rolled out of between the anvil and the cartridge during clamping.Thus, these dimensions are merely exemplary and are not intended to belimiting. The trunnion tabs 2342 and the pivot holes 2700 may have othersizes, shapes and dimensions relative to each other that differ fromsuch exemplary dimensions given herein that nevertheless enable thosecomponents to operate in the unique and novel manner of variousembodiments of the present invention as described herein.

This ability of the trunnion tabs 2342 to travel within their respectivepivot hole 2700 in the side walls of the 2309 of the elongate channel2302 can be appreciated from reference to FIGS. 62-68. As can be seen ineach of those Figures, the closure nut 2440 is in its distal-most openposition. When in that position, the retainer lip 2464 of the closurelock spring is biased under the closure nut 2440 and does not restrictthe travel thereof. FIGS. 62 and 63 illustrate the trunnion tabs 2342adjacent the proximal end wall portions 2702 of the pivot holes. FIGS.65 and 44 illustrate the trunnion tabs 2342 after they have creptsomewhat midway between the proximal end wall portion 2702 and thedistal end wall portion 2704 of the pivot hole 2700. FIGS. 67 and 68illustrate the trunnion tabs 2342 after they have crept to a positionadjacent the distal end wall portions 2704 of the pivot holes 2700.Thus, in various embodiments, the trunnion tabs 2342 are looselyreceived within their respective pivot holes 2700 and capable of movingaxially, laterally and vertically or in combinations of such directionstherein.

FIGS. 69-72 illustrate the anvil 2340 in a closed position. As can beseen in FIG. 70, the trunnion tabs 2342 are in abutting contact with aproximal end wall portion 2702 of the pivot hole 2700. When in thatposition (i.e., when the trunnion tabs 2342 are held in abutting contactwith proximal end wall portion 2702), the staple-forming pockets 2350 inthe bottom surface 2341 of the anvil 2340 are in axial registration withcorresponding staple-receiving pockets 2512 in the cartridge 2500 seatedin the elongate channel 2302 such that when the staples 2534 are fired,they are correctly formed by the corresponding pockets 2350 in the anvil2340. The anvil 2340 is locked in that position by the retainer lip 2464portion of the closure lock spring 2460 as will be discussed in furtherdetail below.

Also in various embodiments, the anvil 2340 is capable of movinglaterally relative to the elongate channel due to manufacturingtolerances in the fabrication of the trunnion tabs 2342 and the pivotholes 2700. As can be seen in FIGS. 44-46, 62, 65, 69, and 73, invarious embodiments, the anvil 2340 is provided with a pair ofdownwardly extending tissue stops 2344. During the clamping process, thetissue stops 2344 essentially perform two functions. One of thefunctions consists of orienting the tissue 2900 within the end effector2300 so as to prevent the tissue 2900 from extending axially into theend effector 2300 such that it extends beyond the innermost staplepockets 2512 in the cartridge 2500 when seated in the elongate channel2302. See FIG. 65. This prevents tissue 2900 from being cut that is notstapled. The other function performed by the tissue stops 2344 is toaxially align the anvil 2340 relative to the elongate channel 2302 andultimately to the cartridge 2500 received therein. As the anvil 2340 isclosed, the tissue stops 2344 serve to contact corresponding alignmentsurfaces 2720 on the side of the elongate channel 2302 and serve tolaterally align the anvil 2340 relative to the elongate channel 2302when the anvil 2340 is closed and clamping tissue 2900 such that thestaple-forming pockets 2350 in the bottom surface 2341 of the anvil 2340are laterally aligned with the corresponding staple-receiving pockets2512 in the cartridge 2500. See FIGS. 69 and 73.

The operation of various embodiments of the present invention will nowbe described with reference to FIGS. 62-71. FIGS. 62-68 illustrate theclosure nut 2440 in an open position. As can be seen in those Figures,when in the open position, the closure nut 2440 is located such that thehook arm 2346 is permitted to move to various positions relative theretothat enable the anvil 2340 to pivot open to permit tissue 2900 to beinserted between the anvil 2340 and the elongated channel 2302 andcartridge 2500 seated therein. When in this position, the distal end2467 of the retainer arm 2466 that is attached to the closure lockspring 2460 is in contact with a ramp surface 2321 formed on theproximal end of the knife assembly 2320. See FIG. 64. As the knifeassembly 2320 moves proximally, the end of the retainer arm 2466contacts the ramp surface 2321 on the proximal end of the knife assembly2320 and serves to cause the retainer arm 2466 to bias the upper portion2462 of the closure lock spring 2460 downward toward the bottom of theelongate channel 2302. When the knife assembly 2320 moves distally awayfrom the retainer arm 2466, the upper portion 2462 of the closure lockspring 2460 is permitted to spring upward to enable the retainer lip2464 to engage the closure nut 2440 as will be further discussed below.

The reader will appreciate that when the end effector 2300 is in theopen positions depicted in FIGS. 62-68, the user can install adisposable cartridge assembly 2500 in the elongate member 2302. Also,when in those positions, the anvil 2340 may be able to move axially,laterally and vertically relative to the elongate channel 2302. Invarious embodiments, when the drive shaft 2402 is rotated in a firstdirection, the closure thread 2406 thereon threadably drives the closurenut 2440 in the proximal direction (direction “B” in FIG. 50) until theclosure threads 2406 disengage the threaded hole 2442 in the closure nut2440. See FIG. 55. As the closure nut 2440 is driven proximally, theclosure hook 2346 on the anvil closure arm 2347 rides up the ramp 2444of the closure nut 2440 until it rides into the radiused portion 2446and contacts the closure tab 2448. Such movement of the closure nut 2440serves to “pull” the anvil 2340 to the closed position. See FIGS. 69-71.When in that position, the trunnion tabs 2342 are in abutting contactwith the proximal end portion 2702 of the pivot holes 2700 and theretainer lip 2464 of the closure lock spring has engaged the distal end2441 of the closure nut 2440 to retain the anvil 2340 in the fullyclosed and axially aligned position. When also in that position, byvirtue of the contact of the tissue stops 2344 with the alignmentsurfaces 2720 on the side walls 2309 of the elongate channel 2302, theanvil 2340 is laterally aligned with the elongate channel 2302 so thatthe staple forming pockets 2350 in the anvil 2340 are laterally alignedwith corresponding the staple-receiving pockets 2512 in the cartridge2500.

As the closure nut 2440 is driven in the proximal direction, theproximal end 2449 of the closure nut 2440 contacts the thrust bearing2434 which forces the clutch plate 2420 in the proximal directionagainst the force of clutch opening spring 2432. Further travel of theclosure nut 2440 in the proximal direction drives the clutch plate 2420onto the tapered sections 2416 of the tapered clutch member 2412 whichcauses the male splines 2418 therein to engage the female splines 2408on the distal drive shaft portion 2402. Such engagement of the malesplines 2418 in the tapered clutch member 2412 with the female splineson the distal drive shaft portion 2402 causes the tapered clutch member2412 and the drive gear 2414 to rotate with the distal drive shaftportion 2402. Drive gear 2414, in turn, rotates the knife screw gear2316 which causes the knife screw to rotate and drive the knife assemblydistally (“A” direction).

As the knife assembly 2320 is driven distally, it cuts the tissue andthe cams 2328 on the wedge sled 2326 serve to drive the staplesupporting drivers 2532 upward which drive the staples 2534 toward theanvil 2340. As the legs 2536 of the staples 2534 are driven into thecorresponding staple-forming pockets 2350 in the anvil 2340, they arefolded over. See FIG. 49.

When the knife assembly 2320 moves distally, the distal end 2467 of theretainer arm 2466 is no longer in contact with the ramp surface 2321 ofthe knife assembly 2320 which enables the retainer arm 2466 and theupper portion 2462 of the closure lock spring 2460 to spring upwardlywhich further enables the retainer lip 2464 on the closure lock spring2460 to retainingly engage the distal end 2441 of the closure nut 2440to prevent it from moving distally. See FIGS. 70 and 71. By virtue ofits contact with the closure nut 2440 which is in contact with thethrust bearing 2434, the retainer lip 2464 serves to retain the clutchassembly 2410 engaged with the distal drive shaft portion 2402 until theknife assembly 2320 once again returns to contact the distal end 2467 ofthe retainer arm 2464. After the knife assembly 2320 has been driven toits final distal position as shown in FIG. 72, it activates aconventional sensor or contact 2313 mounted within the elongate channel2302 and signals the control motor to stop driving the drive shaft 2402.See FIG. 76. Those of ordinary skill in the art will understand that avariety of different control arrangements could be employed to controlthe drive shaft 2402. For example, when the knife assembly 2310 reachesits distal-most position and activates the sensor 2313, the controlsystem 2610 housed within the handle 2006 could automatically reversethe drive motor 2600 therein and cause the drive shaft portion 2402 andknife screw to reverse direction (e.g., move in the proximal “B”direction). In various other embodiments, the control system 2610 maysimply stop the drive motor 2600 and then require the surgeon toactivate a button 2030 to cause the motor 2600 to reverse. In stillother arrangements, the control system 2610 may institute apredetermined timed delay between the time that the reversing sensor2313 is activated and the time that the motor 2600 is reversed.

As the knife assembly 2320 moves in the proximal direction on the knifescrew 2304, the closure threads 2406 on the drive shaft 2402 begin toscrew back into the threaded hole portion 2442 in the closure nut 2440.During this process, the ramp surface 2321 of the knife assembly 2320again contacts the distal end 2467 of the retainer arm 2466 which servesto bias the upper portion 2462 of the closure lock spring 2460 towardthe bottom of the elongate channel 2302 to permit the retainer lip 2464to disengage from the distal end 2441 of the closure nut 2440 therebypermitting the clutch opening spring 2432 to bias the clutch assembly2410 and closure nut 2440 distally. As the closure nut 2440 movesdistally, the closure hook 2346 on the anvil 2340 rides up the ramp 2444on the closure nut 2440 until the closure nut 2440 reaches the openposition wherein the closure tab 2448 is received within the tab reliefgroove 2348 in the bottom surface 2341 of the anvil 2340 and the closurenut 2440 moves the anvil assembly 2372 to the open position. A secondconventional sensor or contact 2315 is mounted within the proximal endportion 2305 of the elongate channel 2302 for sensing when the closurenut 2440 is in the open position and communicates with the motor tocause it to stop. See FIG. 46.

As indicated above, a variety of different motor/control arrangementsmay be employed to power the drive shaft portion 2402. For example, invarious embodiments when the closure trigger 2018 is actuated, that is,drawn in by a user of the instrument 2010, the motor 2600 may commencethe above described closing process. A third sensor 2315′ may be used inthe elongate channel member 2302 to sense when the closure nut 2404 hasmoved into the closed position (shown in FIG. 70). When the third sensor2315′ senses that the closure nut 2440 is in that position, the sensor2315′ may cause the motor 2600 to stop rotating. Thereafter, if thesurgeon is satisfied with the clamping of the tissue in the end effector2300, the surgeon may actuate the firing trigger 2020 or other actuatorarrangement to activate the motor 2600 to rotate the drive shaft 2402which drives the knife screw 2304 in the above-mentioned manner.

Another drive arrangement is depicted in FIGS. 75-77. In thisembodiment, a closure wedge 2440′ is axially moved by a manual driveassembly 2800. More specifically and with reference to FIG. 75, theproximal end 2802 of the drive shaft 2402′ is has a drive gear 2810attached thereto. Although a variety of different gear and motorarrangements may be employed, the drive gear 2810 may be oriented forselective meshing engagement with a gear train or transmission assemblygenerally designated as 2820 that is ultimately driven my motor 2600.The drive shaft 2402′ is movably supported by a proximal spine tubesegment 2820 that is pivotally coupled to the distal spine tube segment2058 as described in various of the U.S. patent applicationsincorporated by reference herein above and rigidly attached to thehousing portions 2007 of the handle 2006. In other arrangements whereinthe end-effector is not capable of articulating travel, the distal spinetube 2058 may be longer and rigidly coupled to the sections 2007 of thehandle 2006. Regardless of which spine tube arrangement is employed, thedrive shaft 2402′ is axially and rotatably received therein such thatthe drive shaft 2402′ can move axially in the distal and proximaldirections and also rotate when engaged with the motor 2600.

Various methods may be employed to mechanically move the drive shaft2402′ in the distal and proximal directions. For example, as shown inFIG. 75, a thrust bearing assembly 2830 may be attached to the driveshaft 2402′ for selective contact by a control linkage assembly 2840. Ascan be seen in that Figure, the control linkage assembly 2840 may belinked to the closure trigger 2018 and capable of biasing the driveshaft 2402′ in the proximal (“B”) direction when the closure 2018 ispivoted in the proximal direction, the control linkage assembly contactsthe thrust bearing and pulls the drive shaft 2402 in the proximaldirection.

Turning next to FIGS. 76 and 77, as can be seen in these Figures, thedistal end 2406′ of the drive shaft is rotatably supported within aclosure wedge 2440′ that is similar in construction as closure nut 2440as described above. In particular, the closure wedge 2440′ has aproximal hole 2442′ and a distal hole portion 2443′ that is larger indiameter than the proximal hole portion 2442′. The distal end 2406′ ofthe drive shaft 2402′ is rotatably supported in the distal hole portion2443′by a bearing 2445′. The distal end portion 2406′ of the drive shaft2406′ is longer than the hole 2403′ such that as the drive shaft 2402′moves distally and proximally, it cannot become disengaged from thewedge 2440′. The wedge 2440′ also has a closure ramp portion 2444′, aradiused portion 2446′, and a closure tab 2448′ formed thereon. As canbe seen in FIGS. 76 and 77, a drive gear 2414′ is attached to the driveshaft 2402′ and is adapted to mesh with the transfer gear 2450 that isin meshing engagement with the knife screw gear 2316.

In these embodiments, when the user wishes to close the anvil 2340, theuser moves the closure trigger 2018 toward the handle 2006. This actioncauses the control linkage assembly 2840 to move the drive shaft 2402′in the proximal direction and pull the wedge 2440′ proximally. As thewedge 2440′ moves proximally, the closure hook 2346 on the proximal end2345 of the anvil 2340 rides up the ramp portion 2444′ thereon until theit is seated in the radiused portion 2446′ of the wedge 2440′. The wedge2440′ gets biased proximally until the retainer lip 2464 engages thedistal end 2441′ of the wedge 2440′ as shown in FIG. 77. When in thatposition, the trunnion tabs 2342 of the anvil 2340 are in engagementwith the proximal end portion 2702 of pivot holes 2700 as describedabove. Also when in that position, the drive gear 2414′ is now inmeshing engagement with the transfer gear 2450 (not shown in FIG. 77)that is in meshing engagement with the knife screw gear 2316. Thus, whenthe drive shaft 2402′ is rotated by activating the control motor, thedrive gear 2414′ serves to drive the transfer gear 2450 and the knifescrew gear 2316 to drive the knife assembly 2320 in the above describedmanner. The closure lock spring 2460 and the motor control sensors inthe elongate channel operate in the above described manner.

After the drive motor 2600 has reversed the rotation of the drive shaft2402′ which drives the knife assembly 2320 proximally back to itsstarting position wherein the ramp surface 2321 contacts the distal end2467 of the retainer arm 2466, the lip 2464 of the closure lock spring2460 is biased downwardly to permit the wedge 2440′ to move distally.The user can then release the closure trigger 2018 which is springbiased to the unactuated position shown in FIG. 43. As the closuretrigger 2018 returns to the unactuated position, the control linkageassembly 2840 permits the drive shaft 2402′ and wedge 2440′ to movedistally and open the anvil 2340 in the above-described manner.

The reader will understand that various embodiments of the presentinvention provide vast improvements over prior end effectors and endeffector drive arrangements. In particular, the various unique and noveldrive system of various embodiments of the present invention permit theanvil and elongated channel components of the end effector to bemanufactured utilizing materials and processes that are more economicalthan other materials and processes used in the past without sacrificingperformance. In addition, by providing an anvil that can travel along aclosing path that is substantially parallel to the elongate channel andstaple cartridge housed therein, reduces the likelihood that the tissuewill be rolled out of position during the initial closing of the anvil.

The invention which is intended to be protected is not to be construedas limited to the particular embodiments disclosed. The embodiments aretherefore to be regarded as illustrative rather than restrictive.Variations and changes may be made by others without departing from thespirit of the present invention. Accordingly, it is expressly intendedthat all such equivalents, variations and changes which fall within thespirit and scope of the present invention as defined in the claims beembraced thereby.

Although the present invention has been described herein in connectionwith certain disclosed embodiments, many modifications and variations tothose embodiments may be implemented. For example, different types ofend effectors may be employed. Also, where materials are disclosed forcertain components, other materials may be used. The foregoingdescription and following claims are intended to cover all suchmodification and variations.

Any patent, publication, or other disclosure material, in whole or inpart, that is said to be incorporated by reference herein isincorporated herein only to the extent that the incorporated materialsdoes not conflict with existing definitions, statements, or otherdisclosure material set forth in this disclosure. As such, and to theextent necessary, the disclosure as explicitly set forth hereinsupersedes any conflicting material incorporated herein by reference.Any material, or portion thereof, that is said to be incorporated byreference herein, but which conflicts with existing definitions,statements, or other disclosure material set forth herein will only beincorporated to the extent that no conflict arises between thatincorporated material and the existing disclosure material.

What is claimed is:
 1. A surgical cutting and fastening instrumentcomprising: an end effector comprising a moveable cutting instrument forcutting an object positioned in the end effector; a main drive shaftassembly connected to the end effector; a gear drive train connected tothe main drive shaft assembly; a main motor for actuating the gear drivetrain; a firing trigger for actuating the main motor; and a tactileposition feedback system for applying force to the firing trigger suchthat the position of the firing trigger is related to the position ofthe cutting instrument in the end effector.
 2. The surgical cutting andfastening instrument of claim 1, wherein the tactile position feedbacksystem includes: an encoder for sensing rotation of the main drive shaftassembly; a second motor whose rotations are controlled based on therotations main drive shaft assembly sensed by the encoder; and anactuating member connected to the second motor, wherein the actuatingmember is for applying the force to the firing trigger such thatposition of the firing trigger is related to the position of the cuttinginstrument in the end effector.
 3. The surgical cutting and fasteninginstrument of claim 2, wherein the actuating member includes a threadedrod.
 4. The surgical cutting and fastening instrument of claim 2,further comprising a run motor sensor for sensing retracting of thefiring trigger, wherein, when retraction of the firing trigger is sensedby the run motor sensor, the main motor is signaled to forward rotate tocause cutting of the object positioned in the end effector by thecutting instrument.
 5. The surgical cutting and fastening instrument ofclaim 4, wherein the run motor sensor comprises a proportional switchsuch that the rate of rotation of the main motor is proportional to theretraction force applied to the firing trigger.
 6. The surgical cuttingand fastening instrument of claim 4, wherein the run motor sensorcomprises an on/off switch.
 7. The surgical cutting and fasteninginstrument of claim 4, further comprising a control circuit forreceiving signals from the encoder related to rotation of the main driveshaft assembly and for sending control signals to the second motor basedon the signals received from the encoder.
 8. The surgical cutting andfastening instrument of claim 7, wherein the control circuit is furtherfor: determining, based on the signals received from the encoder, whenthe cutting instrument has completed a cutting stroke; and determining,based on the signals received from the encoder, when the cuttinginstrument has completed retraction.
 9. The surgical cutting andfastening instrument of claim 1, wherein the end effector includes astaple cartridge.
 10. The surgical cutting and fastening instrument ofclaim 1, wherein the end effector includes a helical drive screw, suchthat forward rotation of the helical drive screw causes the cuttinginstrument to undertake the cutting stroke, and reverse rotation of thehelical drive screw causes the cutting instrument to retract.
 11. Thesurgical cutting and fastening instrument of claim 1, wherein the maindrive shaft assembly includes articulation means for articulating theend effector.
 12. The surgical cutting and fastening instrument of claim1, further comprising a closure trigger separate from the firingtrigger, wherein retraction of the closure trigger causes the endeffector to clamp the object positioned in the end effector.
 13. Thesurgical cutting and fastening instrument of claim 12, furthercomprising a locking mechanism for locking the closure trigger to thehandle.
 14. The surgical cutting and fastening instrument of claim 12,further comprising a mechanical closure system for closing the endeffector when the closure trigger is retracted.
 15. The surgical cuttingand fastening instrument of claim 14, wherein the end effectorcomprises: an elongate channel for carrying the cutting instrument; anda clamping member pivotably connected to the elongate channel.
 16. Thesurgical cutting and fastening instrument of claim 15, wherein themechanical closure system includes: a yoke connected to the closuretrigger; a closure bracket connected to the yoke; a closure tubedisposed in the closure bracket and connected to the clamping member,wherein retraction of the closure trigger causes the closure tube tomove longitudinally such that the clamping member pivots to a clampedposition.
 17. A surgical cutting and fastening instrument comprising: anend effector comprising a moveable cutting instrument for cutting anobject positioned in the end effector; a main drive shaft assemblyconnected to the end effector; and a handle connected to the main driveshaft assembly, wherein the handle comprises: a gear drive trainconnected to the main drive shaft assembly; a main motor for actuatingthe gear drive train; a firing trigger for actuating the main motor; anda tactile position feedback system for applying force to the firingtrigger such that position of the firing trigger is related to theposition of the cutting instrument in the end effector; and a run motorsensor for sensing retracting of the firing trigger, wherein, whenretraction of the firing trigger is sensed by the run motor sensor, themain motor is signaled to forward rotate to cause cutting of the objectpositioned in the end effector by the cutting instrument.
 18. Thesurgical cutting and fastening instrument of claim 17, wherein the runmotor sensor comprises a proportional switch such that the rate ofrotation of the main motor is proportional to the retraction forceapplied to the firing trigger.
 19. The surgical cutting and fasteninginstrument of claim 18, wherein the end effector comprises: an elongatechannel for carrying the cutting instrument; and a clamping memberpivotably connected to the elongate channel.
 20. A surgical cutting andfastening instrument comprising: an end effector comprising a moveablecutting instrument for cutting an object positioned in the end effector.a main drive shaft assembly connected to the end effector; and a handleconnected to the main drive shaft assembly, wherein the handlecomprises: a gear drive train connected to the main drive shaftassembly; a main motor for actuating the gear drive train; a firingtrigger for actuating the main motor; and means for applying force tothe firing trigger such that position of the firing trigger is relatedto the position of the cutting instrument in the end effector.